The subject matter discussed in the background section should not be assumed to be prior art merely as a result of its mention in the background section. Similarly, a problem mentioned in the background section or associated with the subject matter of the background section should not be assumed to have been previously recognized in the prior art. The subject matter in the background section merely represents different approaches that, in and of itself, may also be inventions.
In conventional database systems, users access their data resources in one logical database. A user of such a conventional system typically retrieves data from and stores data on the system using the user's own systems. A user system might remotely access one of a plurality of server systems that might in turn access the database system. Data retrieval from the system might include the issuance of a query from the user system to the database system. The database system might process the request for information received in the query and send to the user system information relevant to the request. The efficient retrieval of accurate information and subsequent delivery of this information to the user system has been and continues to be a goal of administrators of database systems. Unfortunately, conventional database approaches might become inefficient if, for example, updating applications or otherwise changing the functionality of the database system, in the presence of complex data structures.
Accordingly, it is desirable to provide techniques to enable an owner of a database system to maintain the availability of the database system to users while providing changes to the functionality of the same.